In 2009, Mark seemed to be in love with girlfriend Joanna Pacitti, 26, of American Idol Season 8. He told E! News that she was “definitely the one.” But in April 2010 he told E!, "We're no longer together. I'm back on the market. It just wasn't working out. I'm 23, she's 25. I don't know. It just didn't work out."

This past October, Mark and So You Think You Can Dance Season 5 winner Jeanine Mason were spotted by TMZcoming out of a first-date dinner. "How'd you know I was here?" Mark joked with the paparazzi before talking very briefly about his now 20-year-old date, Jeanine. Did things go well with the two of them? "Maybe, maybe," Mark replied.

And over the past year or so there have been rumors that the friendship between Mark and fellow DWTS pro — and SYTYCD alum — Chelsie Hightower, 21, is more than friendship.

In writing about Jake Pavelka’s tearful goodbye on DWTS Season 10, Reality Tea said, "And despite [Jake] calling his partner Chelsie his best friend last night, the two immediately parted ways after cameras stopped rolling. Chelsie however reportedly got a 'long' hug and 'sweet kiss on the cheek' from her new beau Mark Ballas." Musician Mark also dedicated a song “to a very special person," Chelsie while performing a solo stint at The Mint in LA last April. “He gave me a shout-out because we’re close friends,” she told OK!.

Mark and Chelsie often dance together at events, including last month at Mohegan Sun. (Watch their cute video below.)

Recently, Mark tweeted about going “home” to London for the first time in four years. Chelsie tweeted about coming back from London around the same time. Did they go together? Are we stalkers for asking?